| 摘要 |
A page description language is interpreted by an interpreter which outputs successive object definitions. Each object definition is conditionaly added to a display list. Based on certain conditions, the display list is rendered and cleared at various times during the interpretation of the page description. If an object definition describes an image object, the display list is rendered and cleared and the image object is added to the display list. If any objects are clipped in the display list, a corresponding clip object definition output from the interpreter is also ensured to exist within the display list. The display list is also rendered and cleared if it becomes too big in size. Clipping state changes of output object definitions from the interpreter also cause the display list to be rendered and cleared. By conditionally rendering the display list during interpretation, memory, storage, speed and processing requirements are improved for page description processing. |
